1. Field of the Invention
The present invention relates to a clamp instruction method for a work piece or an addition axis of a table which supports a pallet having the work piece mounted thereon.
2. Description of the Related Art
Addition axes of two different directions (usually directions orthogonal to each other) are secured to the above-mentioned table. Conventionally, in a case where working involving rotation of a tool is carried out on a work piece supported directly on the table or via a pallet, a clamp instruction to secure the individual addition axes is generated at a stage before the execution of the working, and an unclamp instruction to release the secured state is generated at a stage when the working is finished.
When a rotational torque to rotate the table in a plane direction as shown in FIG. 3A along with the rotational working with a tool is generated at the time of effecting a three-directional linear movement and two-directional rotational movement on each addition axis, or when a rotational torque to revolve the table itself as shown in FIG. 3B is generated due to pressure or the like from the tool, each addition axis is grasped with substantial pressing force by a coupling portion which couples the addition axis to a drive source, so that the coupled state based on the grasp of the addition axis with the coupling portion is not always broken so that rotation to rotate the table in the plane direction or rotation to revolve the table does not always occur.
That is, even when working a work piece with a tool is carried out, there is not a little case occurring where the working state can be sufficiently supported by the grasp of the addition axis with the coupling portion, so that it is not always necessary to bring about a clamp state to secure the addition axis beforehand at the time of carrying out the working, and an unclamp state to release the clamp state after the working is finished.
Therefore, making a clamp state for each working on a work piece with a tool and making an unclamp state at the stage where the working is finished as in the prior art mean wasting of time in generation of an instruction for a clamp state and achievement thereof and generation of an instruction for an unclamp state and achievement thereof which are not always necessary. Such processes result in causing a lower working efficiency in the overall operation including arrangement of a work piece with respect to a tool and necessary working.